Evaluation on DHP19.

We test 1-stage and 3-stage models with spatio-temporal voxel-grid and constant-count representations. Table REF  reports the Mean Per Joint Precision Error (MPJPE, in mm) and summarizes the results. As reference, we compare to the stereo approach of Calabrese [1]}. As a first observation, our methodology performs only slightly worse than the stereo approach (13mm difference). In this setting, constant-count representation performs better than voxel-grid. In the ablations, we elaborate on the differences between the two representations when different backbones are adopted as feature extractors. Moreover, we provide results for our single stage and 3-stages model and compare them. Table REF  shows that multiple stacked stages and intermediate losses provide sensible performance benefits, at the cost of an increase in computational costs and model size.
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